The present invention relates to flexible, sterile containers, for storing and administering medical solutions in a sterile environment. More particularly, the present invention relates to flexible medical containers for storing and administering IV solutions and having sides which are permanently stretched to enlarge their storage capacity.
Various medical solutions are commonly administered intravenously (via IV) from sterile containers to patients. These solutions may include any medical type fluids, such as replacement body fluids and even solutions containing a medicament (drug). Common packaging for the storage and administration of these solutions includes flexible containers having a compartment for storing the solution. An outlet port is coupled to the compartment for administration and delivery of the solution to the patient through a standard IV arrangement.
Oftentimes, medical solutions consist of a mixed combination of a liquid diluent, e.g., an aqueous dextrose or NaCl solution, and a liquid medicament. Desirably, the medicament and diluent are stored separately in the container under aseptic conditions and are not mixed together until immediately prior to use so as to prevent degradation of the final product. Packaging of the diluent and medicament is often further complicated by the character of the medicament which may be in liquid form and, thus, susceptible to hydraulic pressure on the container, as well as degradation under light or oxygen exposure.
Accordingly, various such medicaments which become unstable with time in solution have typically been separately stored in gas-impermeable vials, containers, or the like prior to their use. Before being administered to a patient, medicaments stored in this fashion must be mixed, or diluted in, a physiological solutions or diluents which are also preserved separately. While able to maintain medicament sterility and effectiveness, separate component storage is cumbersome and involves the risk of bacteriological contamination during handling, mixing, and subsequent administration to a patient. Accordingly, medical containers have been developed which include compartments for storing unstable medicaments and compartments which contain diluent liquids. Immediately prior to IV administration to a patient, the components are placed in communication with one another so that the contents can be mixed together aseptically.
Multiple compartment containers, which allow separate storage of diluents and medicaments are known. Such containers are disclosed, for example, in U.S. Pat. No. 4,608,043 to Larkin, U.S. Pat. No. 5,176,634 to Smith et al. and U.S. Pat. No. 5,462,526 to Barney et al. U.S. Pat. Nos. 4,608,043, 5,176,634 and 5,462,526 are expressly incorporated herein in their entirety by reference. The compartments of the containers disclosed in the foregoing patents are separated from one another by peelable or frangible heat seals. The seals are ruptured by manipulation of the container so that the contents of the compartments can be mixed together to thereby form a solution which is delivered to the patient through a standard IV arrangement.
Solution containers on the market today are generally manufactured of materials comprising PVC plastic. PVC material is generally quite murky in aspect, making it difficult to inspect the contents of a container manufactured of such material. Consequently, inspecting such containers for leaks and moisture contamination is quite difficult. Inspection if further complicated when using multiple compartment containers, where there is a need to verify whether complete mixing of the medicament and diluent has taken place prior to administration to a patient. In addition, various hazardous chemicals are used in the manufacture of PVC material which must be disposed of in an environmentally safe manner. PVC containers must be carefully disposed of following their use, because PVC emits a toxic gas when incinerated and includes a toxic plasticizer that can leach into the surrounding environment if the container is buried in a landfill. This toxic plasticizer is also able to leach into IV solutions, making PVC containers unsuitable for use with several types of medical fluids, and particularly with liquid drugs.
These flexible containers are typically fabricated from a pair of opposing planar sheets which are mated together to form a body or shell. Forming a particular sized body results in a fixed volume capacity. Typically, the containers are fabricated to hold standardized volumes. This works well until a non standard volume is necessary. In this situation, one option is to utilize only a portion of the solution stored in a larger container. However, this option is expensive, wasteful and dangerous. The user must also be very careful to only used the desired quantity or prescription of the contained fluid. In addition, any remaining solution may require specialized disposal.
The containers are also typically fabricated to a predetermined overall outer size or a few common overall sizes. This is generally because the overall size of the container determines its volume capacity, and currently containers are provided in a relatively few predetermined volumes. In addition, the fabrication, handling and sterilization of these containers requires highly complex and expensive machinery. This machinery is designed, in part, to handle the overall dimensions of the container. It is therefore desirable to provide a medical container which has a standard overall outer size and has an enlarged volume capacity relative to the standard size. It is further desirable that the medical container be fabricated using the same machinery and handling equipment as that for standard size containers.
Similar to the single compartment containers, multi-compartment containers are typically constructed with predetermined compartment sizes. The diluent compartment is typically sized to hold a sufficient quantity of diluent to mix with the stored medicament and form a proper solution. The diluent compartment size is also based on a particular dosage or stored quantity of the medical solution. The volume of the diluent compartment may also be limited by the overall outer size of the container which must be constructed to fit the packaging and handling equipment. However, in some applications, it may be desirable to increase the quantity of diluent. Currently this is not possible or requires a second container of diluent. Alternatively, some applications may require additional medicament. It is therefore desirable to provide a multi-compartment medical container that has a standard overall outer size with standardized compartment volume capacities that can be permanently enlarged to increase the volume capacity of at least one of the compartments. It is further desirable that the container be manufactured to a predetermined overall size and configuration to facilitate manufacturing, sterilization and handling by the same machinery and processes
The present invention provides a flexible medical container for storing medical solutions which is capable of being permanently enlarged to increase its storage capacity. The present invention also provides a flexible medical container for storing medical solutions and powders which is manufactured to a standardized overall size and optionally enlarged to increase its storage capacity. By providing a flexible container having a front sheet and a rear sheet which can be permanently stretched, the volume capacity of the container can be increased to a variety of sizes and shapes. By adding a simple, optional, enlarging step to the container manufacturing process, the volume enclosure of some containers may be enlarged while others may be kept at a generally standardized or non-enlarged capacity. This advantageously allows the present containers to be substantially fabricated, handled and administered using current methods and equipment.
In one aspect of the present invention, a flexible container for combined storage and administration of a medical fluid is provided. The flexible container includes a substantially transparent front sheet having a first surface area. The front sheet is constructed from a flexible planar layer of a polymer film. A rear sheet having a second surface area and being constructed from a flexible planar layer of a laminate is disposed opposing the front sheet. The front sheet and the rear sheet are sealably attached together along a common peripheral edge to form a volume enclosure. A port is supported along the common peripheral edge and fluidly connected with the volume enclosure. At least one of the front sheet and the rear sheet is permanently elongated to increase the storage capacity of the volume enclosure and thus, the container.
In another aspect of the present invention, the flexible container includes a substantially transparent front sheet having a first surface area. The front sheet is constructed from a flexible planar layer of a polypropylene-polyethylene copolymer blended with a styrene ethylene-butylene styrene thermoplastic elastomer. A similarly sized rear sheet having a second surface area is disposed opposing the front sheet. The rear sheet is constructed from a flexible planar layer of a laminate including an inner layer of a polypropylene-polyethylene copolymer blended with a styrene ethylene-butylene styrene thermoplastic elastomer. This inner layer is disposed facing the opposing front sheet. The rear sheet also includes an intermediate layer of an aluminum foil and an outer thermoplastic layer having a higher melting point than the inner layer. The front sheet and the rear sheet are sealably attached together along a portion of the common portion of the peripheral edge to form a volume enclosure.
A first peelable seal extends between a first side of the common peripheral edge and an opposing second side of the common peripheral edge. This first peelable seal joins the front sheet and the rear sheet together to form a first compartment within the volume enclosure for containing a diluent. A second peelable seal extends between the opposing first and second sides of the common peripheral edge. This second peelable seal joins the front sheet and the rear sheet together to form a second compartment for containing a medicament and a third outlet compartment. The second compartment is disposed between the first compartment and the outlet compartment.
An outlet port is supported along the common peripheral edge. The outlet port is fluidly connected to the outlet compartment. A diluent port is also supported along the common peripheral edge. The diluent port is fluidly connected with the first compartment through a break in the seal along the common peripheral edge. A medicament port is also supported along the common peripheral edge. A medicament port is fluidly connected with the second compartment through a second break in the seal along the common peripheral edge.
In yet a further aspect of the present invention, a method for forming a flexible container for combined storage and administration of medicaments and diluents for IV solutions is disclosed. The method includes the steps of providing a substantially transparent front sheet and a flexible and vapor impermeable rear sheet. The provided front sheet is constructed from a flexible planar layer of a polymer film. The rear sheet is constructed from a planar multi layer laminate. The front sheet and the rear sheet are sealed together along their common peripheral edge so as to define a volume enclosure.
The method also includes the steps of providing first and second sacrificial ports which are supported along a first side of the common peripheral edge and fluidly connected to the volume enclosure. The first sacrificial port is spaced apart from the second sacrificial port along this first side. The outlet port is supported along a second side of the common peripheral edge and is also fluidly connected to the volume enclosure.
The volume enclosure is expanded through inflation with a pressurized gas to permanently stretch at least the front sheet and to thereby increase the volume capacity of the container. The pressurized gas is then relieved from the expanded container. The permanently stretched volume enclosure is then filled with a second gas. The sacrificial ports and the outlet port are then capped to maintain the container in an expanded configuration.
After the container has been permanently expanded, each of the sacrificial ports may be removed. This step includes removing a portion of the first side along the common peripheral edge. The front sheet is then sealably attached to the rear sheet along the first side inwardly from the sacrificial ports to form a continuous permanent seal about the common peripheral edge.
In yet a further aspect of the present invention, a method for increasing the capacity of a flexible container for storage and administration of medical fluids is disclosed. The method includes providing a flexible container, such as the container of the present invention. The provided container includes a flexible planar front sheet opposing a flexible planar rear sheet along a common plane. The front sheet is sealably attached to the flexible rear sheet along a common peripheral edge to form a volume enclosure. A port is connected to the container and fluidly connected with the volume enclosure. The method includes the step of expanding the volume enclosure to permanently stretch at least the front sheet and thereby increase the volume capacity of the container.
The step of expanding the volume enclosure includes providing a multi-piece tool which is configured for receiving the volume enclosure. The tool includes a lower tool portion and an opposing upper tool portion. The lower tool portion has a lower planar edge surrounding a lower concave region. In a similar configuration, the upper tool portion has an upper concave region with surrounding upper planar edge. The lower and upper planar edges are generally opposed and configured to capture the common peripheral edge. The container is sandwiched between the tool such portions with rear sheet facing the lower concave region and the front sheet facing the upper concave region. The volume enclosure is then inflated with a pressurized gas to permanently stretch the front and rear sheets outwardly and against the respective concave regions of the tool. The volume enclosure is maintained inflated for a time sufficient to overcome substantial elastic rebounding.
In yet a further aspect of the present invention, a second method for forming a flexible container for combined storage and administration of medicaments and diluents for IV solutions is disclosed. The method includes providing a flexible and substantially transparent front sheet constructed from a planar layer of a polymer. A flexible and vapor impermeable rear sheet constructed from a planar multi-layer laminate is also provided. The front sheet and the rear sheet are sealed together along a portion of a common peripheral edge to define a volume enclosure. The front sheet and the rear sheets are heated in a first localized area to fuse them together along the heated first localized area and thereby form a first peelable seal. This first seal extends between a first side of the common peripheral edge and an opposing second side of the peripheral edge. The first seal separably joins the front sheet to the rear sheet and thereby forms a first compartment within the volume enclosure for containing a diluent. The front and rear sheets are also heated along a second localized area to form a second peelable seal. The second peelable seal extends between the first side and the opposing second side of the common peripheral edge and separably joins the front and rear sheets together to thereby form a second compartment for containing a medicament. The second compartment is disposed between the first compartment and the outlet compartment.
The method also includes providing a first sacrificial port interposed between the front and rear sheets and in communication with the first compartment. A second sacrificial port is also interposed between the front and rear sheets. However, the second sacrificial port is spaced apart from the first sacrificial port and is fluidly connected with the second compartment. An outlet port is also interposed between the front and rear sheets. The outlet port is fluidly connected with the outlet compartment. The portion of the volume enclosure forming the first compartment is then expanded to permanently stretch the front sheet and the rear sheet and to thereby increase the volume capacity of the first compartment.